With the computer parts consuming more and more power, choosing the correct power supply for your system is very important. A wrong power supply can make your computer freeze, crash, reset from out of the blue and overheat (because the power supply has an ultimate role in the airflow inside the PC – a lot of people aren’t aware of this).

OCZ has two high-performance power supply series, PowerStream and ModStream. PowerStream series offers 420-, 520- and 600 W models and has overvoltage trimpots, a feature for die-hard overclockers. ModStream, on the other hand, offers 450- and 520 W models (with 550 W and 620 W peak loads, respectively) and doesn’t offer overvoltage configuration, however this series has a modular cabling system, where you plug on the power supply just the cable you will really need. Removing unnecessary cables from inside the computer helps a lot the airflow inside your PC. Another difference between these two series is the size and location of the power supply fan. PowerStream series uses a regular 80 mm fan located on the back of the power supply, while ModStream series uses a 120 mm fan located on the bottom of the power supply.

OCZ ModStream 520 W Power SupplyFigure 1: OCZ ModStream 520 W power supply box.

In Figure 2, you can see ModStream 520 W from OCZ. Usually the power supply fan is located on the back of the power supply. On this power supply, the fan is located on its bottom (on the picture the power supply is upside down), while its back is almost completely opened, protected by a grill. This allows a better airflow. Also this power supply uses a big 120 mm fan, which is more silent than 80 mm fans. This fan is transparent with blue LEDs that lights the fan when you turn on your system.

OCZ ModStream 520 W Power SupplyFigure 2: OCZ ModStream 520 W power supply.

On the front of the power supply you will find the connectors for the modular cabling system. As we mentioned, you need to install only the cables you will actually need, so no loose cables inside the computer case blocking the airflow.

OCZ ModStream 520 W Power SupplyFigure 3: OCZ ModStream 520 W power supply, front view.

A piece of advice: as you can see, there are two six-pin squared connectors with different colors (one is light blue, used by PCI Express video cards auxiliary power, and the other one is light blue, used by Serial ATA hard drives). Pay close attention when using this connector. When we installed this power supply we mixed this connection and installed the auxiliary power from our video card (dark blue) on the connector targeted to Serial ATA power (light blue). It took us a while to figure out why our computer wasn’t turning on.

Gabriel Torres is a Brazilian best-selling ICT expert, with 24 books published. He started his online career in 1996, when he launched Clube do Hardware, which is one of the oldest and largest websites about technology in Brazil. He created Hardware Secrets in 1999 to expand his knowledge outside his home country.